Battery monomer, manufacturing method of battery monomer, battery and power utilization device

Abstract

The invention discloses a battery monomer, a manufacturing method of the battery monomer, a battery and a power utilization device. The single battery comprises a first shell, the first shell comprises a first bottom plate and a first side plate, and a first flange edge is formed on the side, away from the first bottom plate, of the first side plate; the second shell comprises a second bottom plate and a second side plate, a second flange edge is formed on the side, away from the first bottom plate, of the second side plate, the second flange edge is connected with the first flange edge, and the first shell and the second shell are matched to form a containing space; the naked battery cell is arranged in the accommodating space; wherein the shortest distance between the connecting position of the first flange edge and the second flange edge and the first side plate or the second side plate is L1, the sum of the height of the first shell and the height of the second shell is L2, and L1: L2 is not smaller than 1% and not larger than 50%. Through the mode, a top cover in a conventional single battery is omitted, and the volume ratio of the battery core in the single battery is increased, so that the energy storable in unit volume of the single battery is increased.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery cell, a method for manufacturing a battery cell, a battery, and an electrical device. Background Art

[0002] Batteries have been widely used in electric vehicles, mobile devices, energy storage devices and other electrical devices due to their advantages such as long cycle life and long storage time. However, as the demand for battery safety and energy storage performance in electrical devices increases, the problem of how to improve the safety and energy storage performance of battery cells needs to be solved urgently. Summary of the invention

[0003] In view of the above problems, the present application provides a battery cell, a method for manufacturing a battery cell, a battery and an electrical device, which can solve the problem of how to improve the safety and energy storage performance of the battery cell.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a battery cell, the battery cell includes: a first shell, the first shell includes a first bottom plate and a first side plate extending along the four sides of the first bottom plate, and a first flange edge is formed on the side of the first side plate away from the first bottom plate; a second shell, the second shell includes a second bottom plate and a second side plate extending along the four sides of the second bottom plate, and a second flange edge is formed on the side of the second side plate away from the first bottom plate, the second flange edge is connected to the first flange edge, and the first shell and the second shell cooperate to form a accommodating space; a bare cell, the bare cell is arranged in the accommodating space; wherein, the closest distance from the connection position of the first flange edge and the second flange edge to the first side plate or the second side plate is L1, the sum of the heights of the first shell and the second shell is L2, and L1:L2 is not less than 1% and not more than 50%.

[0005] Through the above method, the top cover in the conventional battery cell is omitted, and the bare battery cell is accommodated by cooperating with the first shell and the second shell. The structure can be more compact, and the volume ratio of the battery cell in the battery cell is increased, thereby increasing the energy that can be stored in the battery cell per unit volume; the setting of the first flange edge and the second flange edge also improves the safety of the first shell and the second shell when they are connected.

[0006] In some embodiments, a ratio of a height of the first side panel to a thickness of the first side panel is not greater than 500; and / or a ratio of a height of the second side panel to a thickness of the second side panel is not greater than 500.

[0007] Through the above-mentioned method, the difficulty in manufacturing the first shell and / or the second shell can be reduced and the yield rate can be improved.

[0008] In some embodiments, the height of the first side panel is different from the height of the second side panel.

[0009] By means of the above method, the depth of the first shell is different from the depth of the second shell, and the shell with a smaller depth has a higher strength, which corresponds to the area with high strength requirements and can increase the service life of the battery cell.

[0010] In some embodiments, the distance from the edge of the first flange to the first side panel is not less than 0.5 mm, and the distance from the edge of the second flange to the second side panel is not less than 0.5 mm.

[0011] Through the above method, it can be ensured that the first flange edge and the second flange edge have a certain length, ensuring the connection between the first flange edge and the second flange edge without affecting the bare battery cell, thereby enhancing the safety when the first flange edge and the second flange edge are connected.

[0012] In some embodiments, the first flange edge is away from the edge of the first side plate, and the distance between the first flange edge and the second flange edge is not less than 0.1 mm, and the second flange edge is away from the edge of the first side plate, and the distance between the second flange edge and the first flange edge is not less than 0.1 mm.

[0013] By means of the above method, it is ensured that the position where the first flange edge is connected to the second flange edge is not at the edge position, thereby ensuring the sealing of the accommodating space.

[0014] In some embodiments, the first flange edge is away from the edge of the first side panel, and the distance between the first flange edge and the connection position of the second flange edge is no more than 3 mm; the second flange edge is away from the edge of the first side panel, and the distance between the second flange edge and the connection position of the first flange edge is no more than 3 mm.

[0015] By means of the above method, the distance between the connection point between the first flange edge and the second flange edge and the first flange edge and the second flange edge is limited, so as to prevent the distance from being too large, save materials and reduce the occupied space of the battery cell.

[0016] In some embodiments, the first flange edge is connected to the first side plate via a first chamfer, and / or the second flange edge is connected to the second side plate via a second chamfer.

[0017] In the above manner, the first flange edge is connected to the first side plate by the first chamfer, and the second flange edge is connected to the second side plate by the second chamfer. When the bare cell is placed in the accommodation space, it can be guided into the accommodation space by the first chamfer or the second chamfer, and the bare cell is easier to install. At the same time, the chamfer can also reduce the residual stress at the connection between the first flange edge / the second flange edge and the first shell / the second shell, reduce the possibility of cracks, improve the stress at the connection between the first flange edge / the second flange edge and the first shell / the second shell, and improve the structural strength.

[0018] In some embodiments, the first chamfer and / or the second chamfer is a rounded corner, and the radius of the first chamfer and / or the second chamfer is greater than or equal to 0.1 mm.

[0019] Through the above-mentioned method, the rounded corners can better reduce the stress concentration at the chamfers and make the dimensional error of the chamfers smaller, which will not affect the assembly accuracy of the battery cells.

[0020] In some embodiments, a first thickened portion is provided on a side of the first flange edge away from the second flange edge, and / or a second thickened portion is provided on a side of the second flange edge away from the first flange edge, and at least part of the first thickened portion and / or the second thickened portion is located at the connection between the first flange edge and the second flange edge.

[0021] Through the above manner, the first thickened portion and the second thickened portion can provide protection for the position where the first flange edge and the second flange edge are connected, so that the structural strength and stability are enhanced.

[0022] In some embodiments, the thickness of the first flange edge is greater than the thickness of the first side plate and / or the first bottom plate, and the thickness of the second flange edge is greater than the thickness of the second side plate and / or the second bottom plate.

[0023] In the above manner, the structural strength of the first flange and the second flange is higher, and the thicker thickness also enhances the stability of the position where the first flange and the second flange are connected. For example, when affected by welding heat, the thicker thickness can have a larger heat capacity, so that the structural performance is not easily reduced due to overheating. As a result, the connection between the first flange and the second flange is more stable, thereby improving the stability of the battery cell.

[0024] In some embodiments, the first flange edge is connected to the second flange edge by welding, and the connection position between the first flange edge and the second flange edge is the position where the first flange edge and the second flange edge are welded.

[0025] In the above manner, welding connection is the best connection method between the first shell and the second shell in the battery cell, which can ensure that the first flange edge and the second flange edge are tightly connected together without generating gaps, thereby achieving a good sealing effect.

[0026] In a second aspect, the present application provides a method for manufacturing a battery cell, characterized in that the manufacturing method includes: assembling a first shell and a second shell, the first shell including a first bottom plate and a first side plate extending around the first bottom plate, a first flange edge being formed on a side of the first side plate away from the first bottom plate; the second shell including a second bottom plate and a second side plate extending around the second bottom plate, a second flange edge being formed on a side of the second side plate away from the first bottom plate, the second flange edge being in conflict with the first flange edge; connecting the first flange edge and the second flange edge; the closest distance from the connection position of the first flange edge and the second flange edge to the first side plate or the second side plate is L1, the sum of the heights of the first shell and the second shell is L2, and L1:L2 is not less than 1% and not more than 50%.

[0027] Through the above method, the top cover in the conventional battery cell is omitted, and the bare battery cell is accommodated by cooperating with the first shell and the second shell. The structure can be more compact, and the volume ratio of the battery cell in the battery cell is increased, thereby increasing the energy that can be stored in the battery cell per unit volume; the setting of the first flange edge and the second flange edge also improves the safety of the first shell and the second shell when they are connected.

[0028] In some embodiments, the manufacturing method further includes: cutting the connected first flange edge and the second flange edge, removing an edge of the first flange edge away from the first side plate, and removing an edge of the second flange edge away from the second side plate.

[0029] By adopting the above method, the space occupied by the flange edge can be reduced, thereby reducing the space occupied by the battery cell.

[0030] In some embodiments, a first positioning groove is provided at an edge of the first flange away from the first side plate, and a second positioning groove is provided at an edge of the second flange away from the second side plate. In the step of assembling the first shell and the second shell, the positions of the first positioning groove and the second positioning groove overlap; in the step of cutting the connected first flange and second flange, the first positioning groove and the second positioning groove are cut off.

[0031] Through the above method, the first shell and the second shell can be accurately aligned, thereby improving the alignment efficiency and accuracy of the first shell and the second shell during the manufacturing process.

[0032] In some embodiments, the first positioning groove and the second positioning groove are polygonal grooves, arc-shaped grooves or angular grooves.

[0033] Through the above method, the first positioning groove and the second positioning groove can be flexibly arranged, and the shapes can be adjusted according to needs.

[0034] In some embodiments, the distance between the first positioning groove and the nearest position of the first side plate to the edge of the first flange away from the first side plate is not less than 0.5 mm, and the distance between the second positioning groove and the nearest position of the second side plate to the edge of the second flange away from the second side plate is not less than 0.5 mm.

[0035] Through the above-mentioned method, the accuracy of the first shell and the second shell during the alignment process can be ensured, and the misalignment will not occur due to the first positioning groove and the second positioning groove being too small.

[0036] In a third aspect, the present application provides a battery, the battery comprising the battery cell in the above embodiment, or the battery comprising a battery cell manufactured by the method for manufacturing the battery cell in the above embodiment.

[0037] In a fourth aspect, the present application provides an electrical device, which includes the battery of the above embodiment, and the battery is used to supply power to the electrical device, or the battery is used to store or release electrical energy for the electrical device.

[0038] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. In addition, the same reference numerals are used throughout the drawings to represent the same components.

[0040] In the figure:

[0041] Figure 1 is a schematic diagram of a vehicle according to some embodiments;

[0042] Figure 2 is an exploded schematic diagram of a battery according to some embodiments;

[0043] Figure 3 is a schematic diagram of an exploded structure of a battery cell according to some embodiments;

[0044] Figure 4 is a schematic structural diagram of a battery cell according to some embodiments;

[0045] Figure 5 is a schematic side view of a battery cell according to some embodiments;

[0046] Figure 6 yes Figure 5 A magnified schematic diagram of the middle A area;

[0047] Figure 7 is a schematic diagram of a partial cross-sectional structure of a first housing according to some embodiments;

[0048] Figure 8 is a schematic diagram of a partial cross-sectional structure of a second housing according to some embodiments;

[0049] Fig. 9 yes Figure 5 An enlarged schematic diagram of another embodiment of the region A;

[0050] Fig.10 is a flow chart of a method for making a battery cell according to some embodiments;

[0051] Fig.11 is a flow chart of a method for manufacturing a battery cell according to other embodiments;

[0052] Fig.12 is a schematic diagram of a top view of the structure of the first housing in S11 according to some embodiments;

[0053] Fig.13 is a schematic diagram of the bottom view structure of the second shell in S11 according to some embodiments.

[0054] The reference numerals in the specific implementation manner are as follows:

[0055] 1000, vehicle; 200, controller; 300, motor; 100, battery; 10, housing; 11, first part; 12, second part;

[0056] 20. Battery cell; 21. Battery cell; 22. First shell; 221. First bottom plate; 222. First side plate; 223. First flange; 224. Connection position between first flange and second flange; 225. First positioning groove; 226. First thickened portion; 23. Second shell; 231. Second bottom plate; 232. Second side plate; 233. Second flange; 235. Second positioning groove; 236. Second thickened portion. DETAILED DESCRIPTION

[0057] The following is a detailed description of the implementation of the technical solution of the present application. The following implementation is only used to more clearly illustrate the technical solution of the present application, and is therefore only used as an example, and cannot be used to limit the scope of protection of the present application.

[0058] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific implementation methods and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0059] In the description of the implementation methods of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the implementation methods of the present application, unless otherwise clearly and specifically defined, the term "multiple" refers to more than two (including two), similarly, "multiple groups" refers to more than two (including two), and "multiple pieces" refers to more than two (including two).

[0060] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0061] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0062] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0063] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0064] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0065] During the manufacturing process of a battery cell, after the bare cell is placed in the shell, welding and other processes are generally used to package the top cover and the shell into one. However, due to material limitations, the depth of the housing space of the shell for accommodating the bare cell is certain, which limits the thickness of the bare cell, that is, limits the volume ratio of the bare cell in the battery cell. In addition, when the connection position between the shell and the top cover is close to the bare cell, the bare cell may be damaged during the connection. For example, a high-temperature welding pool may partially melt the bare cell, affecting the safety of the battery cell. When the distance between the set connection position and the cell is far, the volume of the structure from the connection position between the top cover and the shell to the bare cell is increased, which reduces the volume ratio of the bare cell in the battery cell, thereby reducing the amount of energy that can be stored in the battery per unit volume.

[0066] Based on the above considerations, in order to solve the technical problems existing in battery cells in the prior art, the present application proposes a battery cell that can reduce the possibility of damage to the battery cell and has a higher energy storage performance.

[0067] The present application provides an electric device, which may include but is not limited to mobile phones, cars, tablets, laptops, electric toys, electric tools, battery cars, electric cars, ships, spacecraft, etc. Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc., and spacecraft may include airplanes, rockets, space shuttles and spacecraft, etc. Among them, the electric device may include a battery, and the electric device may provide electric energy through the battery to realize the corresponding function of the electric device.

[0068] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in one embodiment of the present application.

[0069] Please refer to Figure 1 , Figure 1 is a schematic diagram of the structure of a vehicle according to some embodiments.

[0070] The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and operating power requirements of the vehicle 1000 during driving.

[0071] In some embodiments of the present application, the battery 100 can be used not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0072] Please refer to Figure 2 , Figure 2 Exploded diagram of a battery provided in some embodiments of the present application. In order to improve the performance of an electrical device, the present application also provides a battery 100. The shape of the battery 100 includes but is not limited to a square. In other embodiments, the shape of the battery 100 may also be cylindrical, square, or any other shape.

[0073] In some embodiments, the battery 100 may include a case 10 and a battery cell 20, and the battery cell 20 is contained in the case 10. The case 10 is used to provide a storage space for the battery cell 20, and the case 10 may adopt a variety of structures. In some embodiments, the case 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20. The second part 12 may be a hollow structure with one end open, the first part 11 may be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 may also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the case 10 formed by the first part 11 and the second part 12 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0074] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0075] Each battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0076] The manufacturing methods of the battery cell 20 include stacking and winding, that is, the battery cell 20 is divided into stacking cells and winding cells. The stacking battery has a uniform current collection effect, a small internal resistance of the battery, and a large specific power, but it has extremely high requirements for mold precision, high equipment investment, and a relatively complex process, and low production efficiency. The winding battery is simple to make, and the production and assembly processes have general requirements for equipment precision, high production efficiency, and low cost. In terms of performance, the winding battery has excellent high and low temperature performance, charges very quickly, has an ultra-long life, a stable high output voltage, a solid structure, and strong shock resistance.

[0077] See also Figure 3 , Figure 3 Schematic diagram of the exploded structure of a battery cell according to some embodiments. The battery cell 20 refers to the smallest unit constituting a battery. The battery cell 20 includes a bare cell 21, a first shell 22, a second shell 23 and other functional components.

[0078] See also Figures 4 to 6 , Figure 4 is a schematic structural diagram of a battery cell according to some embodiments, Figure 5 is a schematic side view of a battery cell according to some embodiments, Figure 6 yes Figure 5 A magnified schematic diagram of the area in the middle. Figure 3The battery cell 20 includes a first shell 22, a second shell 23 and a bare cell 21. The first shell 22 includes a first bottom plate 221 and a first side plate 222 extending around the first bottom plate 221, and a first flange 223 is formed on the side of the first side plate 222 away from the first bottom plate 221. The second shell 23 includes a second bottom plate 231 and a second side plate 232 extending around the second bottom plate 231, and a second flange 233 is formed on the side of the second side plate 232 away from the first bottom plate 221. The second flange 233 is connected to the first flange 223, and the first shell 22 and the second shell 23 cooperate to form a accommodating space. The bare cell 21 is arranged in the accommodating space. Among them, the closest distance from the connection position of the first flange 223 and the second flange 233 to the first side plate 222 or the second side plate 232 is L1, and the height sum of the first shell 22 and the second shell 23 is L2, and L1:L2 is not less than 1% and not more than 50%. The value of L1:L2 may be 1%, 2%, 3%, 4%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 27%, 30%, 33%, 35%, 38%, 40%, 42%, 45%, 47%, 49%, 50%. Alternatively, the value of L1:L2 is within the range of any two of the above values, for example, the value of L1:L2 is not less than 1% and not more than 30%, not less than 5% and not more than 45%, not less than 20% and not more than 40%, not less than 15% and not more than 35%, etc.

[0079] Specifically, the bare cell 21 is a component in the battery cell 20 where electrochemical reactions occur. The bare cell 21 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the main body of the battery cell 21, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute a tab. The positive electrode tab and the negative electrode tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery cell 20, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0080] The first shell 22 cooperates with the second shell 23 to form a accommodating space, wherein the formed accommodating space can be used to accommodate the bare battery cell 21, electrolyte and other components. One or more bare batteries 21 may be contained in the accommodating space. The first side plate 222 extends along the four sides of the first bottom plate 221. In some embodiments, the first side plate 222 is perpendicular to the first bottom plate 221. The first side plate 222 cooperates with the first bottom plate 221 to form a groove structure with an opening. A chamfered structure may be provided at the connection between the first side plate 222 and the first bottom plate 221. The chamfered structure may be a first fillet structure R1 or a bevel structure. When the chamfered structure is a first fillet structure R1, the radius of the first fillet structure R1 is not less than 0.1 mm. For example, the radius of the first fillet structure R1 is 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm. Alternatively, the radius of the first fillet structure R1 is between any two of the above values, for example, the radius of the first fillet structure R1 is not less than 0.1 mm and not more than 1 mm; or the radius of the first fillet structure R1 is not less than 0.2 mm and not more than 1.5 mm, etc. In some embodiments, the radius of the soft glue structure R1 is not more than 2 mm. The edge of the first side plate 222 away from the first bottom plate 221 is provided with a first flange edge 223, and the first flange edge 223 can be perpendicular to the first side plate 222 and parallel to the first bottom plate 221. The second side plate 232 extends around the second bottom plate 231. In some embodiments, the second side plate 232 is perpendicular to the second bottom plate 231. The second side plate 232 cooperates with the second bottom plate 231 to form two groove structures with openings. A chamfered structure may be provided at the connection between the second side plate 232 and the second bottom plate 231. The chamfered structure may be a second fillet structure R2 or a bevel structure. When the chamfered structure is a second rounded structure R2, the radius of the second rounded structure R2 is not less than 0.1 mm. For example, the radius of the second rounded structure R2 is 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm. Alternatively, the radius of the second rounded structure R2 is between any two of the above values, for example, the radius of the second rounded structure R2 is not less than 0.1 mm and not greater than 1 mm; or the radius of the second rounded structure R2 is not less than 0.2 mm and not greater than 1.5 mm, etc. In some embodiments, the radius of the first rounded structure R1 is not greater than 2 mm. The second side plate 232 is provided with a second flange edge 233 at an edge away from the second bottom plate 231, and the second flange edge 233 can be perpendicular to the second side plate 232 and parallel to the second bottom plate 231. The first shell 22 and the second shell 23 can be independent components, and the opening provided on the first shell 22 is opposite to the opening provided on the second shell 23 to form an accommodating space. The first side plate 222 , the first flange edge 223 and the first bottom plate 221 may be an integrally formed structure, that is, they are made of the same piece of material and are a whole, rather than being formed by connection.The second side plate 232, the second flange edge 233 and the second bottom plate 231 may also be an integrally formed structure. The first side plate 222 may be multiple, for example, four, respectively located in different directions of the first bottom plate 221. The first flange edge 223 corresponds to the first side plate 222 and is arranged around the multiple first side plates 222. The second side plate 232 may be multiple, for example, four, respectively located in different directions of the second bottom plate 231. The second flange edge 233 corresponds to the second side plate 232 and is arranged around the multiple second side plates 232.

[0081] The first shell 22 and the second shell 23 can be in various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, etc. Specifically, the shapes of the first shell 22 and the second shell 23 can be determined according to the specific shape and size of the bare battery cell 21. The first shell 22 and the second shell 23 can be made of various materials, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0082] Functional components such as electrode terminals may be provided on at least one of the first shell 22 and the second shell 23. The electrode terminal can be used to electrically connect to the bare battery cell 21 for outputting or inputting electrical energy of the battery cell 20. In some embodiments, the electrode terminal may include a positive electrode terminal and a negative electrode terminal for outputting current and connecting to an external circuit. In some embodiments, a breathable valve assembly for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value may also be provided on the first shell 22 and / or the second shell 23. In some embodiments, an insulating member may also be provided on the inner side of the first shell 22 and / or the second shell 23, and the insulating member may be used to isolate the electrical connection components in the first shell 22 and / or the second shell 23 from the second shell 23 and / or the first shell 22 to reduce the risk of short circuit. Exemplarily, the insulating member may be plastic, rubber, etc.

[0083] The connection method between the second shell 23 and the first shell 22 includes, but is not limited to, welding connection, adhesive connection, etc. In one embodiment, the second shell 23 can cover the first shell 22, and the second shell 23 and the first shell 22 are fixedly connected by welding the first flange 223 and the second flange 233. When the second shell 23 is connected to the first shell 22, the second shell 23 cooperates with the first shell 22 to close the accommodation space, and the accommodation space is isolated from the external environment.

[0084] The connection position 224 between the first flange 223 and the second flange 233 refers to the position where a bonding force is generated between the first flange 223 and the second flange 233 when the first flange 223 and the second flange 233 are connected. For example, when the first flange 223 and the second flange 233 are welded, the connection position between the first flange 223 and the second flange 233 refers to the position of the weld, and the weld connects the first flange 223 and the second flange 233 as a whole. The closest distance from the connection position between the first flange 223 and the second flange 233 to the first side plate 222 or the second side plate 232 is the closest distance from the connection position between the first flange 223 and the second flange 233 to the outer surface of the first side plate 222 or the second side plate 232.

[0085] Those skilled in the art can select the distance between the connection position between the second shell 23 and the first shell 22 and the bare cell 21 according to product and process requirements. If the distance L1 between the connection position between the second shell 23 and the first shell 22 and the bare cell 21 is too small, the connection process between the second shell 23 and the first shell 22 may affect the bare cell 21, thereby damaging the bare cell 21 and affecting safety performance. If the distance L1 between the connection position between the second shell 23 and the first shell 22 and the bare cell 21 is too large, the volume of the structure between the connection position between the second shell 23 and the first shell 22 and the bare cell 21 will increase, that is, the volume proportion of the bare cell 21 in the battery cell 20 is reduced, thereby reducing the energy that can be stored in the battery cell 20 per unit volume.

[0086] In the above manner, the battery cell 20 is formed into a whole by the bare cell 21, the first shell 22, and the second shell 23. The top cover in the conventional battery cell 20 is omitted, and the bare cell 21 is accommodated by the first shell 22 and the second shell 23. The structure can be more compact, and the volume ratio of the bare cell 21 in the battery cell 20 is increased, thereby increasing the energy that can be stored in the unit volume of the battery cell 20; the distance L1 between the connection position 224 of the first flange edge 223 and the second flange edge 233 and the bare cell 21 will not be too small, and the connection process of the second shell 23 and the first shell 22 is not easy to affect the bare cell 21, reducing the possibility of damage to the bare cell 21. At the same time, the distance L1 between the connection position of the second shell 23 and the first shell 22 and the bare cell 21 will not be too large, and the structure of the first shell 22 and the second shell 23 can be more compact, which increases the volume ratio of the bare cell 21 in the battery cell 20, thereby increasing the energy that can be stored in the unit volume of the battery cell 20. In addition, since the connection position 224 between the first flange edge 223 and the second flange edge 233 is between the first flange edge 223 and the second flange edge 233, it is far away from the bare battery cell 21, which reduces the impact on the bare battery cell 21 when the first shell 22 and the second shell 23 are connected, and improves the safety of the first shell 22 and the second shell 23 when they are connected.

[0087] like Figure 7 and Figure 8 As shown, Figure 7 is a schematic diagram of a partial cross-sectional structure of a first shell according to some embodiments, Figure 8 : is a schematic diagram of a partial cross-sectional structure of the second shell according to some embodiments. According to some embodiments of the present application, the ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 is not greater than 500. For example, the ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 can be 500, 490, 480, 470, 460, 450, 400, 350, 300, 250, 200, 150, 100, 50, 40, 30, 20, 10, 5, 2. Alternatively, the ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 can be between the ranges of any two of the above values, for example, the ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 is 500-200, or the ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 is 450-150. And / or, the ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 is not greater than 500. For example, the ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 may be 500, 490, 480, 470, 460, 450, 400, 350, 300, 250, 200, 150, 100, 50, 40, 30, 20, 10, 5, 2. Alternatively, the ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 may be between the ranges of any two of the above values, for example, the ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 is 500-200, or the ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 is 450-150. In some embodiments, the ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 is not less than 2, and the ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 is not less than 2. In summary, the overall thickness of the battery cell 20 is the sum of the thickness of the first shell 22 and the thickness of the second shell 23, that is, the sum of the height H1 of the first side plate 222 and the height H2 of the second side plate 232. The ratio of the overall thickness of the battery cell 20 to the thickness L42 of the first side plate 222 or the second side plate 232 is less than or not greater than 1000. The height H1 of the first side plate 222 is the length of the first side plate 222 extending in a direction perpendicular to the first bottom plate 221, and is also the distance between a side surface of the first bottom plate 221 away from the first flange edge 223 to a side surface of the first flange edge 223 away from the first bottom plate 221, as Figure 7The thickness L32 of the first side plate 222 is the length between the inner surface of the first side plate 222 facing the accommodating space and the outer surface of the first side plate 222 outside the accommodating space, and its direction is as follows: Figure 7 , or from right to left as shown in . The ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 is the value of the height H1 of the first side plate 222 divided by the thickness L32 of the first side plate 222. Similarly, the height H2 of the second side plate 232 is the length of the second side plate 232 extending in a direction perpendicular to the second bottom plate 231, and is also the distance between the side surface of the second bottom plate 231 away from the second flange edge 233 and the side surface of the second flange edge 233 away from the second bottom plate 231. The direction is as shown in FIG. Figure 8 The thickness L42 of the second side plate 232 is the length between the inner surface of the second side plate 232 facing the accommodating space and the outer surface of the second side plate 232 outside the accommodating space, as shown in FIG. Figure 8 The direction from left to right as shown in , or the direction from right to left. The ratio of the height H2 of the second side plate 232 to the thickness L42 of the second side plate 232 is the value of the height H2 of the second side plate 232 divided by the thickness L42 of the second side plate 232. The first shell 22 and the second shell 23 are generally formed by stretching a whole piece of material. If the ratio of the height H2 of the first side plate 222 or the second side plate 232 to the thickness is too large, it is easy for the thickness L42 of the first side plate 222 or the second side plate 232 to be too small, and it is easy to break. The height H2 of the first side plate 222 is the height of the first shell 22, the height of the second side plate 232 is the height of the second shell 23, and the sum of the heights L2 of the first shell 22 and the second shell 23 is the sum of the height H1 of the first side plate 222 and the height H2 of the second side plate 232.

[0088] Through the above-mentioned method, the difficulty in manufacturing the first shell 22 and / or the second shell 23 can be reduced, and the yield rate can be improved.

[0089] According to some embodiments of the present application, a height H1 of the first side plate 222 is different from a height H2 of the second side plate 232 .

[0090] In some embodiments, the height H1 of the first side plate 222 may be less than the height H2 of the second side plate 232. The direction of the height H1 of the first side plate 222 is the same as the depth direction of the first shell 22, and the height H1 of the first side plate 222 determines the depth of the first shell 22. When the same piece of material is stretched to form a shell with a groove structure, since the main stretching position is at the side wall of the shell, the smaller the depth of the shell, the greater the thickness of the side plate of the shell and the higher the strength. When the depth of the first shell 22 is small, that is, when the height H1 of the first side plate 222 is small, the thickness L32 of the first side plate 222 will be large. At this time, the strength of the first side plate 222 will be higher than that of the second side plate 232, and the bare battery 21 can be better protected. Similarly, in some embodiments, the height H2 of the second side plate 232 may also be less than the height H1 of the first side plate 222. In some embodiments, the ratio of the height to the thickness of the side plate with a smaller height is not less than 2, and the ratio of the height to the thickness of the side plate with a larger height is greater than the ratio of the height to the thickness of the side plate with a smaller height.

[0091] By means of the above method, the depth of the first shell 22 is different from the depth of the second shell 23 . The shell with a smaller depth has a higher strength, which corresponds to the area with high strength requirements, and can increase the service life of the battery cell 20 .

[0092] According to some embodiments of the present application, a distance L3 from the edge of the first flange 223 to the first side plate 222 is not less than 0.5 mm, and a distance L4 from the edge of the second flange 233 to the second side plate 232 is not less than 0.5 mm.

[0093] The distance L3 from the edge of the first flange 223 to the first side plate 222 can be regarded as the length of the first flange 223 extending outward from the first side plate 222. Figure 7 In the direction from left to right in the middle. And, it is the distance from the edge of the first flange edge 223 away from the first side plate 222 to the outside of the first side plate 222. The distance L3 from the edge of the first flange edge 223 to the first side plate 222 can be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 12 mm, 15 mm, 18 mm, 20 mm, 25 mm, 30 mm. Alternatively, the distance L3 from the edge of the first flange edge 223 to the first side plate 222 can be within the range between any two of the above, for example, it can be 0.5 mm to 20 mm, it can be 2 mm to 30 mm, etc. The distance L4 from the edge of the second flange edge 233 to the second side plate 232 can be regarded as the length of the second flange edge 233 extending outward from the second side plate 232, such as Figure 8In the direction from left to right in the middle. And, it is the distance from the edge of the second flange edge 233 away from the second side plate 232 to the outer side of the second side plate 232. The distance L4 from the edge of the second flange edge 233 to the second side plate 232 can be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 12 mm, 15 mm, 18 mm, 20 mm, 25 mm, 30 mm. Alternatively, the distance L4 from the edge of the second flange edge 233 to the second side plate 232 can be within the range between any two of the above, for example, it can be 0.5 mm to 20 mm, it can be 2 mm to 30 mm, etc.

[0094] Through the above method, it can be ensured that the first flange edge 223 and the second flange edge 233 have a certain length, ensuring the connection between the first flange edge 223 and the second flange edge 233 without affecting the bare battery cell 21, thereby enhancing the safety when the first flange edge 223 and the second flange edge 233 are connected.

[0095] According to some embodiments of the present application, the distance between the first flange edge 223 and the connection position 224 between the first flange edge 223 and the second flange edge 233 is not less than 0.1 mm, and can be 0.1 mm, 0.2 mm, 0.3 mm, 0.5 mm, 0.7 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, or 5 mm. Alternatively, the distance between the first flange edge 223 and the connection position 224 between the first flange edge 223 and the second flange edge 233 can be between any two of the above numerical ranges, for example, 0.1 mm to 3 mm, or 0.5 mm to 2 mm. The second flange edge 233 is away from the edge of the first side plate 222, and the distance between the second flange edge 233 and the first flange edge 223 is not less than 0.1 mm, and can be 0.1 mm, 0.2 mm, 0.3 mm, 0.5 mm, 0.7 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, 5 mm. The connection position of the second flange edge 233 and the first flange edge 223 is the connection position 224 of the first flange edge 223 and the second flange edge 233. Alternatively, the second flange edge 233 is away from the edge of the first side plate 222, and the distance between the second flange edge 233 and the first flange edge 223 can be between any two of the above numerical ranges, for example, 0.1 mm to 3 mm, 0.5 mm to 2 mm.

[0096] The distance between the edge of the first flange 223 away from the first side plate 222 and the position where the first flange 223 is connected to the second flange 233 is the distance from the position where the first flange 223 is connected to the second flange 233 to the edge of the first flange 223. The distance between the edge of the second flange 233 away from the second side plate 232 and the position where the first flange 223 is connected to the second flange 233 is the distance from the position where the first flange 223 is connected to the second flange 233 to the edge of the second flange 233. During the manufacturing process of the battery cell 20, the first flange 223 and the second flange 233 are cut to remove the excess edges. However, during the cutting process, the position where the first flange 223 is connected to the second flange 233 cannot be cut, otherwise it is easy for the accommodating space to be unsealed. Therefore, it is necessary to keep a certain distance between the position where the first flange 223 is connected to the second flange 233 and the edges of the first flange 223 and the second flange 233.

[0097] By means of the above method, it is ensured that the connection position 224 between the first flange edge 223 and the second flange edge 233 is not at the edge position, thereby ensuring the sealing of the accommodating space.

[0098] According to some embodiments of the present application, the first flange edge 223 is away from the edge of the first side plate 222, and the distance to the connection position 224 between the first flange edge 223 and the second flange edge 233 is not greater than 3 mm, and the second flange edge 233 is away from the edge of the first side plate 222, and the distance to the connection position between the second flange edge 233 and the first flange edge 223 is not greater than 3 mm.

[0099] The maximum distance between the edge of the first flange 223 away from the first side plate 222 and the connection position 224 of the first flange 223 and the second flange 233 is 3 mm, and the maximum distance between the edge of the second flange 233 away from the first side plate 222 and the connection position between the second flange 233 and the first flange 223 is 3 mm. If this distance exceeds 3 mm, it will occupy a larger space, which will increase the volume of the battery cell 20, but the volume of the bare battery cell 21 will not increase, which will reduce the energy that can be stored in the unit volume of the battery cell 20. In addition, if this distance is too large, it will also increase the use of materials and cause waste. The distance between the edge of the first flange 223 away from the first side plate 222 and the position where the first flange 223 connects to the second flange 233 can be equal to the distance between the edge of the second flange 233 away from the first side plate 222 and the position where the second flange 233 connects to the first flange 223.

[0100] In the above manner, the distance between the connection point between the first flange edge 223 and the second flange edge 233 and the first flange edge 223 and the second flange edge 233 is limited to prevent this distance from being too large, thereby saving materials and reducing the occupied space of the battery cell 20.

[0101] According to some embodiments of the present application, the first flange edge 223 is connected to the first side plate 222 via a first chamfer R3, and / or the second flange edge 233 is connected to the second side plate 232 via a second chamfer R4.

[0102] The first chamfer R3 includes an inner chamfer and / or an outer chamfer. When an inner chamfer is provided, the inner chamfer is located on the side of the first side plate 222 facing the accommodating space. When an outer chamfer is provided, the outer chamfer is located on the side of the first side plate 222 away from the accommodating space. One end of the inner chamfer and / or the outer chamfer is connected to the first side plate 222, and the other end is connected to the first flange edge 223. The second chamfer R4 also includes an inner chamfer and / or an outer chamfer. When an inner chamfer is provided, the inner chamfer is located on the side of the second side plate 232 facing the accommodating space. When an outer chamfer is provided, the outer chamfer is located on the side of the second side plate 232 away from the accommodating space. One end of the inner chamfer and / or the outer chamfer is connected to the second side plate 232, and the other end is connected to the second flange edge 233.

[0103] Further, the shape of the inner chamfer and / or the outer chamfer can be set according to actual conditions. For example, in one specific embodiment, the chamfer includes an inner chamfer and an outer chamfer. The inner chamfer is a bevel. The outer chamfer is a bevel. In another specific embodiment, the chamfer includes an inner chamfer and an outer chamfer, the inner chamfer is a rounded angle, and the outer chamfer is a bevel. In another other specific embodiment, the chamfer includes an inner chamfer and an outer chamfer, the inner chamfer is a bevel, and the outer chamfer is a rounded angle.

[0104] Through the above method, the first flange edge 223 is connected to the first side plate 222 through the first chamfer R3, and the second flange edge 233 is connected to the second side plate 232 through the second chamfer R4. When the bare cell 21 is placed in the accommodation space, it can be guided into the accommodation space by the first chamfer R3 or the second chamfer R4, and the bare cell 21 is easier to install. At the same time, the chamfer can also reduce the residual stress at the connection between the first flange edge 223 / the second flange edge 233 and the first shell 22 / the second shell 23, reduce the possibility of cracks, improve the stress at the connection between the first flange edge 223 / the second flange edge 233 and the first shell 22 / the second shell 23, and improve the structural strength.

[0105] According to some embodiments of the present application, the first chamfer R3 and / or the second chamfer R4 are rounded corners, and the radius of the first chamfer R3 and / or the second chamfer R4 is greater than or equal to 0.1 mm. The first chamfer R3 and / or the second chamfer R4 are outer chamfers. The radius of the first chamfer R3 and / or the second chamfer R4 is, for example, 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, or 2 mm.

[0106] Those skilled in the art can select the radius of the fillet according to product and process requirements. If the radius of the fillet is set too small, stress concentration is likely to occur at the chamfer, thereby causing cracks. If the radius of the fillet is set too large, the dimensional error at the chamfer will increase as the size increases, thereby affecting the assembly accuracy of the battery cell 20.

[0107] Through the above method, the rounded corners can better reduce the stress concentration at the chamfers and make the dimensional error of the chamfers smaller, which will not affect the assembly accuracy of the battery cell 20.

[0108] like Fig. 9 As shown, Fig. 9 yes Figure 5 An enlarged schematic diagram of another embodiment of the region A in the middle. According to some embodiments of the present application, a first thickened portion 226 is provided on a side of the first flange edge 223 away from the second flange edge 233, and / or a second thickened portion 236 is provided on a side of the second flange edge 233 away from the first flange edge 223. At least a portion of the first thickened portion 226 and / or the second thickened portion 236 is located at the connection between the first flange edge 223 and the second flange edge 233.

[0109] The first thickened portion 226 and the second thickened portion 236 may be a metal strip, which is compacted and connected to the first flange 223 or the second flange 233. The width of the first thickened portion 226 is smaller than the width of the first flange 223, and the width of the second thickened portion 236 is smaller than the width of the second flange 233. Before the first flange 223 and the second flange 233 are connected, the first thickened portion 226 is arranged on a side of the first flange 223 away from the second flange 233, and the second thickened portion 236 is arranged on a side of the second flange 233 away from the first flange 223. The first thickened portion 226 may be compacted on the first flange 223, and the second thickened portion 236 may be compacted on the second flange 233. When the first flange 223 and the second flange 233 are connected, the first thickened portion 226 may be connected to the first flange 223 at the same time, and the second thickened portion 236 may be connected to the second flange 233 at the same time. The first thickened portion 226 and the second thickened portion 236 can well enhance the strength of the first flange edge 223 and the second flange edge 233. For example, when affected by welding heat, the thicker thickness can have a larger heat capacity, so that the structural performance is not easily reduced due to overheating.

[0110] In the above manner, the first thickened portion 226 and the second thickened portion 236 can provide protection for the connection position 224 of the first flange edge 223 and the second flange edge 233, so that the strength and stability of the first flange edge 223 and the second flange edge 233 of the structure are enhanced.

[0111] According to some embodiments of the present application, the thickness L33 of the first flange edge 223 is greater than the thickness L32 of the first side plate 222 and / or the thickness L31 of the first bottom plate 221 , and the thickness L43 of the second flange edge 233 is greater than the thickness L42 of the second side plate 232 and / or the thickness L41 of the second bottom plate 231 .

[0112] The thickness L33 of the first flange edge 223 may be greater than the thickness L32 of the first side plate 222; or, the thickness L33 of the first flange edge 223 may be greater than the thickness L31 of the first bottom plate 221; or, the thickness L33 of the first flange edge 223 may be greater than the thickness of any one of the first side plate 222 and the first bottom plate 221. The thickness direction of the first flange edge 223 and the first bottom plate 221 is the same, both of which are perpendicular to the first bottom plate 221, that is, Figure 7 The second flange edge 233 has the same thickness direction as the second bottom plate 231, both of which are perpendicular to the second bottom plate 231, that is, Figure 8 The first flange 223 and the second flange 233 are the parts that connect the first shell 22 and the second shell 23, and are also the parts that ensure the sealing of the accommodation space. Therefore, increasing the thickness of the first flange 223 and the second flange 233 is to increase the strength of the first flange 223 and the second flange 233 to ensure the stability of the connection, thereby ensuring the sealing of the accommodation space. For example, when affected by welding heat, a thicker thickness can have a larger heat capacity, so that the structural performance is not easily reduced due to overheating.

[0113] In the above manner, the structural strength of the first flange edge 223 and the second flange edge 233 is higher, and the thicker thickness also enhances the stability of the connection position 224 of the first flange edge 223 and the second flange edge 233. For example, when affected by welding heat, the thicker thickness can have a larger heat capacity, so that the structural performance is not easily reduced due to overheating. As a result, the connection between the first flange edge 223 and the second flange edge 233 is more stable, thereby improving the stability of the battery cell 20.

[0114] According to some embodiments of the present application, the first flange edge 223 and the second flange edge 233 are connected by welding, and the connection position between the first flange edge 223 and the second flange edge 233 is the position where the first flange edge 223 and the second flange edge 233 are welded.

[0115] The position where the first flange edge 223 and the second flange edge 233 are welded may also be referred to as a weld mark position, which is a position where a welding mark is left.

[0116] In the above manner, welding connection is the best connection method between the first shell 22 and the second shell 23 in the battery cell 20, which can ensure that the first flange edge 223 and the second flange edge 233 are tightly connected together without generating gaps, thereby achieving a good sealing effect.

[0117] like Fig.10 As shown, Fig.10 is a flow chart of a method for manufacturing a battery cell according to some embodiments. The present application also provides a method for manufacturing a battery cell 20, the manufacturing method comprising:

[0118] In S11, the first shell 22 and the second shell 23 are assembled. The first shell 22 includes a first bottom plate 221 and a first side plate 222 extending around the first bottom plate 221, and a first flange 223 is formed on the side of the first side plate 222 away from the first bottom plate 221. The second shell 23 includes a second bottom plate 231 and a second side plate 232 extending around the second bottom plate 231, and a second flange 233 is formed on the side of the second side plate 232 away from the first bottom plate 221, and the second flange 233 is in conflict with the first flange 223.

[0119] In S12, the first flange 223 is connected to the second flange 233. The shortest distance between the connection position of the first flange 223 and the second flange 233 and the first side plate 222 or the second side plate 232 is L1, the height sum of the first shell 22 and the second shell 23 is L2, and L1:L2 is not less than 1% and not more than 50%.

[0120] Before S11 , the process may further include the step of placing the bare cell 21 into the first shell 22 or the second shell 23 .

[0121] Through the above-mentioned method, the top cover in the conventional battery cell 20 is omitted, and the bare battery cell 21 is accommodated by the cooperation of the first shell 22 and the second shell 23. The structure can be more compact, and the volume ratio of the battery cell in the battery cell 20 is increased, thereby increasing the energy that can be stored in the battery cell 20 per unit volume; the setting of the first flange edge 223 and the second flange edge 233 also improves the safety of the first shell 22 and the second shell 23 when they are connected.

[0122] like Fig.11 As shown, Fig.11Flow chart of a method for manufacturing a battery cell according to other embodiments. According to some embodiments of the present application, the method for manufacturing a battery cell 20 includes, in addition to S11 and S12, S13: cutting the first flange edge 223 and the second flange edge 233 that have been connected, removing the edge of the first flange edge 223 away from the first side plate 222, and removing the edge of the second flange edge 233 away from the second side plate 232.

[0123] In order to facilitate the assembly of the first shell 22 and the second shell 23, the first flange 223 and the second flange 233 thereon are larger when the first shell 22 and the second shell 23 are manufactured. After the larger first flange 223 and the second flange 233 are connected, there will be some redundant parts on the edges. Removing this part can reduce the space occupied by the flange, thereby reducing the volume of the battery cell 20.

[0124] By adopting the above-mentioned method, the space occupied by the flange edge can be reduced, thereby reducing the space occupied by the battery cell 20 .

[0125] like Fig.12 and Fig.13 As shown, Fig.12 is a schematic diagram of a top view of the structure of the first housing in S11 according to some embodiments, Fig.13 It is a schematic diagram of the bottom view structure of the second shell in S11 according to some embodiments. According to some embodiments of the present application, the edge of the first flange edge 223 away from the first side plate 222 is provided with a first positioning groove 225, and the edge of the second flange edge 233 away from the second side plate 232 is provided with a second positioning groove 235. In the step S11 of assembling the first shell 22 and the second shell 23, the positions of the first positioning groove 225 and the second positioning groove 235 overlap. In the step S13 of cutting the first flange edge 223 and the second flange edge 233 after the connection is completed, the first positioning groove 225 and the second positioning groove 235 are cut off.

[0126] The first positioning groove 225 is a notch formed at the edge of the first flange 223 away from the first side plate 222, and the notch has a certain shape. The second positioning groove 235 is a notch formed at the edge of the second flange 233 away from the second side plate 232, and the notch has a certain shape. The second positioning groove 235 has the same shape as the first positioning groove 225. When the second positioning groove 235 overlaps with the first positioning groove 225, it can be determined that the first shell 22 and the second shell 23 are aligned. There can be multiple first positioning grooves 225 and second positioning grooves 235, and they can be set at different positions of the first flange 223 and the second flange 233. In addition, multiple first positioning grooves 225 can be set on the first flange 223 connected to different first side plates 222, and multiple second positioning grooves 235 can be set on the second flange 233 connected to different second side plates.

[0127] Through the above method, the first shell 22 and the second shell 23 can be accurately aligned, thereby improving the alignment efficiency and accuracy of the first shell 22 and the second shell 23 during the manufacturing process.

[0128] According to some embodiments of the present application, the first positioning groove 225 and the second positioning groove 235 are polygonal grooves, arc-shaped grooves or angular grooves.

[0129] The polygonal groove is, for example, a rectangular groove, a square groove, a diamond groove or other quadrilateral grooves, a pentagonal groove, etc. The angular groove is a groove having only one corner except for the edge.

[0130] Through the above-mentioned method, the first positioning groove 225 and the second positioning groove 235 can be flexibly arranged, and the shapes can be adjusted according to the requirements.

[0131] According to some embodiments of the present application, the present application further provides a battery 100, comprising a battery cell 20 as described in any of the above schemes, or a battery cell 20 produced by the method for producing the above battery cell 20. The battery 100 can be used as an energy storage device. An energy storage device is a device for storing and / or releasing electrical energy. For example, an energy storage device can be used in a power grid system to store electrical energy when the power supply of the power grid is greater than the demand, and to release electrical energy when the power supply of the power grid is less than the demand. In addition, the energy storage device can also be used as a power source for household, commercial, industrial use, etc.

[0132] According to some embodiments of the present application, the present application further provides an electric device, including the battery 100 described in any of the above solutions, the battery 100 is used to supply power to the electric device. Alternatively, the battery 100 is used to store or release electrical energy for the electric device.

[0133] The electrical device may be any of the aforementioned devices or systems using the battery 100. For example, the electrical device may include but is not limited to mobile phones, cars, tablets, laptop computers, electric toys, electric tools, battery vehicles, electric cars, ships, spacecraft, etc.

[0134] Finally, in a specific application scenario, such as Figure 3 As shown, the battery cell 20 includes a bare cell 21, a first shell 22, and a second shell 23. The first shell 22 and the second shell 23 are assembled to form an accommodation space. The bare cell 21 is arranged in the accommodation space. The battery cell 20 includes a first shell 22, a second shell 23, and a bare cell 21. The first shell 22 includes a first bottom plate 221 and a first side plate 222 extending around the first bottom plate 221, and a first flange edge 223 is formed on the side of the first side plate 222 away from the first bottom plate 221. The second shell 23 includes a second bottom plate 231 and a second side plate 232 extending around the second bottom plate 231, and a second flange edge 233 is formed on the side of the second side plate 232 away from the first bottom plate 221. The second flange edge 233 is connected to the first flange edge 223, and the first shell 22 and the second shell 23 cooperate to form an accommodation space. The bare cell 21 is arranged in the accommodation space. The shortest distance between the connection position of the first flange edge 223 and the second flange edge 233 and the first side plate 222 or the second side plate 232 is L1, the sum of the heights of the first shell 22 and the second shell 23 is L2, and L1:L2 is not less than 1% and not more than 50%. The ratio of the height H1 of the first side plate 222 to the thickness L32 of the first side plate 222 is not more than 500. The height H1 of the first side plate 222 is different from the height H2 of the second side plate 232. The ratio of the height to the thickness of the side plate with a smaller height is not less than 2, and the ratio of the height to the thickness of the side plate with a larger height is greater than the ratio of the height to the thickness of the side plate with a smaller height.

[0135] In the above manner, the battery cell 20 is formed into a whole by the bare cell 21, the first shell 22, and the second shell 23. The top cover in the conventional battery cell 20 is omitted, and the bare cell 21 is accommodated by the first shell 22 and the second shell 23. The structure can be more compact, and the volume ratio of the bare cell 21 in the battery cell 20 is increased, thereby increasing the energy that can be stored in the unit volume of the battery cell 20; the distance L1 between the connection position 224 of the first flange edge 223 and the second flange edge 233 and the bare cell 21 will not be too small, and the connection process of the second shell 23 and the first shell 22 is not easy to affect the bare cell 21, reducing the possibility of damage to the bare cell 21. At the same time, the distance L1 between the connection position of the second shell 23 and the first shell 22 and the bare cell 21 will not be too large, and the structure of the first shell 22 and the second shell 23 can be more compact, which increases the volume ratio of the bare cell 21 in the battery cell 20, thereby increasing the energy that can be stored in the unit volume of the battery cell 20. In addition, since the connection position 224 between the first flange edge 223 and the second flange edge 233 is located between the first flange edge 223 and the second flange edge 233, it is far from the bare cell 21, which reduces the impact on the bare cell 21 when the first shell 22 and the second shell 23 are connected, and improves the safety of the first shell 22 and the second shell 23 when they are connected. The depth of the first shell 22 is different from the depth of the second shell 23, and the shell with a smaller depth has a higher strength, which corresponds to the high-strength requirement area and can increase the service life of the battery cell 20.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the various embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: The battery cell comprises: A first shell, the first shell comprising a first bottom plate and a first side plate extending around the first bottom plate, a first flange edge being formed on a side of the first side plate away from the first bottom plate; A second shell, the second shell comprising a second bottom plate and a second side plate extending around the second bottom plate, a second flange edge being formed on a side of the second side plate away from the first bottom plate, the second flange edge being connected to the first flange edge, and the first shell and the second shell cooperate to form an accommodating space; A bare battery cell, wherein the bare battery cell is disposed in the accommodating space; The shortest distance from the connection position of the first flange edge and the second flange edge to the first side plate or the second side plate is L1, the sum of the heights of the first shell and the second shell is L2, and L1:L2 is not less than 1% and not more than 50%.

2. The battery cell according to claim 1, characterized in that: A ratio of a height of the first side panel to a thickness of the first side panel is not greater than 500; and / or a ratio of a height of the second side panel to a thickness of the second side panel is not greater than 500.

3. The battery cell according to claim 1 or 2, characterized in that: The height of the first side plate is different from the height of the second side plate.

4. The battery cell according to any one of claims 1 to 3, characterized in that: The distance from the edge of the first flange to the first side plate is not less than 0.5 mm, and the distance from the edge of the second flange to the second side plate is not less than 0.5 mm.

5. The battery cell according to any one of claims 1 to 4, characterized in that: The first flange edge is away from the edge of the first side panel, and the distance between the first flange edge and the connection position of the second flange edge is not less than 0.1 mm; the second flange edge is away from the edge of the first side panel, and the distance between the second flange edge and the connection position of the first flange edge is not less than 0.1 mm.

6. The battery cell according to claim 5, characterized in that: The first flange edge is away from the edge of the first side panel, and the distance between the first flange edge and the connection position of the second flange edge is not greater than 3 mm; the second flange edge is away from the edge of the first side panel, and the distance between the second flange edge and the connection position of the first flange edge is not greater than 3 mm.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The first flange edge is connected to the first side plate via a first chamfer, and / or the second flange edge is connected to the second side plate via a second chamfer.

8. The battery cell according to claim 7, characterized in that: The first chamfer and / or the second chamfer is a rounded corner, and a radius of the first chamfer and / or the second chamfer is greater than or equal to 0.1 mm.

9. The battery cell according to any one of claims 1 to 8, characterized in that: A first thickened portion is provided on a side of the first flange edge away from the second flange edge, and / or a second thickened portion is provided on a side of the second flange edge away from the first flange edge, and at least part of the first thickened portion and / or the second thickened portion is located at the connection between the first flange edge and the second flange edge.

10. The battery cell according to any one of claims 1 to 9, characterized in that: The thickness of the first flange edge is greater than the thickness of the first side plate and / or the first bottom plate, and the thickness of the second flange edge is greater than the thickness of the second side plate and / or the second bottom plate.

11. The battery cell according to any one of claims 1 to 10, characterized in that: The first flange edge is connected to the second flange edge by welding, and the connection position of the first flange edge and the second flange edge is the position where the first flange edge and the second flange edge are welded.

12. A method for manufacturing a battery cell, characterized in that: The production method comprises: The first shell and the second shell are assembled together, wherein the first shell includes a first bottom plate and a first side plate extending along the periphery of the first bottom plate, and a first flange is formed on a side of the first side plate away from the first bottom plate; the second shell includes a second bottom plate and a second side plate extending along the periphery of the second bottom plate, and a second flange is formed on a side of the second side plate away from the first bottom plate, and the second flange is in conflict with the first flange; The first flange edge is connected to the second flange edge; the shortest distance from the connection position of the first flange edge and the second flange edge to the first side panel or the second side panel is L1, the sum of the heights of the first shell and the second shell is L2, and L1:L2 is not less than 1% and not more than 50%.

13. The method for manufacturing a battery cell according to claim 12, characterized in that: The production method further comprises: The first flange edge and the second flange edge that have been connected are cut to remove an edge of the first flange edge away from the first side plate, and to remove an edge of the second flange edge away from the second side plate.

14. The method for manufacturing a battery cell according to claim 13, characterized in that: The edge of the first flange away from the first side plate is provided with a first positioning groove, the edge of the second flange away from the second side plate is provided with a second positioning groove, and in the step of assembling the first shell and the second shell, the first positioning groove and the second positioning groove are overlapped; In the step of cutting the first flange edge and the second flange edge that have been connected, the first positioning groove and the second positioning groove are cut off.

15. The method for manufacturing a battery cell according to claim 14, characterized in that: The first positioning groove and the second positioning groove are polygonal grooves, arc-shaped grooves or angular grooves.

16. The method for manufacturing a battery cell according to claim 14 or 15, characterized in that: The distance between the first positioning groove and the closest position to the first side panel to the edge of the first flange away from the first side panel is not less than 0.5 mm, and the distance between the second positioning groove and the closest position to the second side panel to the edge of the second flange away from the second side panel is not less than 0.5 mm.

17. A battery, characterized in that: The battery comprises the battery cell according to any one of claims 1 to 11, or the battery comprises the battery cell manufactured by the method for manufacturing a battery cell according to any one of claims 12 to 15.

18. An electrical device, characterized in that: The electrical device comprises the battery according to claim 17.

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